Various additives have been used in animal feed in attempts to enhance the nutritional value of the feed. U.S. Pat. No. 6,207,217 relates to animal nutrition compositions that include a polyhydroxyalkanoate (PHA) for improving the metabolizable energy content of the feed. This patent teaches that PHA can be accumulated in corn or an oilseed and that a plant part comprising the PHA can be fed to livestock for the animal industry. U.S. Pat. No. 4,186,212 relates to “Animal feed containing high molecular weight aliphatic alcohols” to enhance metabolic energy available in a ruminant diet. Steers are exemplified. U.S. Pat. No. 4,172,148, relating to ruminant feeds, relates to the use of cellulosic roughage together with trichloroethyl esters of essential amino acids. Sheeps are the exemplified animals. U.S. Pat. No. 4,171,385 relates to animal feed blocks containing a fiber source and magnesium oxide (so that the feed can be made in block form). Heifers are exemplified.
Despite painstaking efforts and care, many current diets used by (and commercially available to) zoos often do not exactly match the natural diets of wild browsers and other herbivores. The use of commonly available feeds, although healthful to domestic livestock, can cause zoo animals to develop health disorders such as ruminal acidosis and, possibly, peracute mortality syndrome.
Problems such as ruminal acidosis are not limited to zoo animals. Even domesticated animals such as cows can experience such problems, and various attempts have been made to treat such conditions. For example, U.S. Pat. No. 6,017,564, entitled “Treatment of stressed animals with dihydroxyquinoline compounds,” relates to treating sick ruminants by administering this compound with a ration. Heifers are exemplified. U.S. Pat. No. 4,112,069, entitled “Treatment of ruminants,” relates to the administration of the microorganism Peptococcus asaccharolyticus together with a ration or feed.
The art mentions that some amount of cottonseed can be included as one of many components in some domesticated animal feeds. U.S. Pat. No. 4,321,278, for example, shows cotton seed hulls as one of several components in sheep food, but that patent relates to increasing the protein content of such feed by chlorination and ammoniation. U.S. Pat. No. 5,908,634 relates to domesticated animal feed containing molasses, bentonite, and zeolite. Cottonseed and various other meals can be used there as the source of solvent extracted and extruded protein. Hay and various other components can be included with those feeds. U.S. Pat. No. 3,988,480 relates to acetic-acid treated protein meals for animals such as sheep. Because of the acid treatment, these feeds are said to resist microbial breakdown in the rumen. Cottonseed and various other meals can be used as the initial protein source to be acid treated according to that invention. U.S. Pat. No. 6,299,913 relates to a feedstock for improving the lactational performance of dairy cows. Cottonseed meal can be included as one component of the feeds, but an essential feature of those feeds are certain cations and anions in specified ratios.
However, the art as discussed above does not suggest that cottonseed hulls (without an “active ingredient”) could be used to improve digestive function and thus cure ruminal acidosis and other digestive ailments. The art actually teaches against this, as some other active ingredient is included, in many of the above embodiments, to alleviate acidosis. Furthermore, the art did not show or suggest that cottonseed hulls could be used as feed for zoo animals, and the art certainly did not show or suggest that cottonseed hulls, as a simple feed, could be used to improve digestive function to treat or prevent ruminal acidosis and the like in zoo animals.
There are several commercially available feeds for zoo animals. One example is MAZURI diets from PURINA. Some of these diets are intended for consumption by primates and llamas, for example. A diet called OMNIVORE ZOO FEED “A” comprises ground soybean hulls. Some other commercially available diets even include wood in their feed, but that is not provided explicitly for physical form needs.
This illustrates that wild browsers have natural diets, feeding behaviors, and related morphologies and physiologies that differ substantially from domesticated animals. Cows and other grazers were bred and raised to eat grass, hay, corn, and the like. On the other hand, typical non-domesticated browsers naturally prefer to eat leafy tissues, fresh flowers, and other like plant parts, over grass plants and grains. Thus, feeds and possible treatments for sick domesticated animals cannot be readily applied to captive browsers made ill because of inappropriate diet composition and physical form. In addition, many of these treatments, some of which might be mentioned above, attempt to treat symptoms, but they do not address the root cause of the illness.
The art does acknowledge that hay and concentrated supplements might cause digestive problems in animals that do not naturally eat hay. For example, Clauss et al. observed that grass and hay are typically broken down into long, fiber-like particles that form a “fibrous raft” in the rumen of a grazer, while browse is typically broken down into polygonal particles that cannot form a fibrous raft. Clauss, M., M. Lechner-Doll, E. J. Flach, J. Wisser, and J. M. Hatt (2002), “Digestive tract pathology of captive giraffe (Giraffa camelopardalis): an unifying hypothesis,” in Proceedings of European Association of Zoo and Wildlife Veterinarians (EAZWV), 4th Scientific Meeting, May 8-12, 2002, Heidelberg, Germany. Clauss et al. also observed that captive giraffes had lower food intakes when fed only hay and a pelleted diet, as compared to those offered additional browse or linseed/flaxseed extraction chips. However, the art has yet to offer a practical, economical solution to these problems. It can be understood that much more time, money, and resources have been devoted to developing diets and treatments for domesticated animals because of the great financial implications dietary problems and the like can have in the beef industry, for example. However, much less is currently known about the exact nutritional needs of zoo animals and how to meet these needs in a practical, economical manner.